Question

factorise it!! Please please

Answer 1

1) $y {}^{2} - 12 \sqrt{3} y - 105$

$y {}^{2} - 7 \sqrt{3} y -5\sqrt{3} y- 105$

$y(y - 7 \sqrt{3} ) - 5 \sqrt{3} (y - 7 \sqrt{3} )$

$(y - 5 \sqrt{3} )(y - 7 \sqrt{3} )$

$2) \: \: \: \: \: \: - a {}^{2} - 2a + 84$

a = 1 , b = -2, c = 84

Now apply quadratic formula...

$x = - b + - \sqrt{ {b}^{2} - 4ac} \div 2a$

$- ( - 2) + - \sqrt{( - 2) {}^{2} - 4(1)(84) } \div 2(1)$

$2 + - \sqrt{4 - 336} \div 2$

$so \: x =( 2 + \sqrt{332} ) \div 2 \: \: \: and \: \: \: (2 - \sqrt{332} ) \div 2$

Answer 2

Answer:

this is in rd sharma book